Telegraphone



H. B. WIER AND W. H. CAPEN.

TELEGRAFHONE.

APPLICATION FILED 0012s, 191e.

1,366,61 '7. Patented Jan'. 25, 1921.

2 SHEETS-SHEET 1.

A Wfl/fam H cape/7 H. B. WIER AND W. H. CAPEN.

TELEGRAPHONE.

APPLICATION FILED OCT.23,1916.

Patented Ja'n. 25, 1921.

2 SHEETS-SHEET 2.

UNiTED STATES PATENT OFFICE.

HARRY B. WIER, OF PLAINFIEID, NEW JERSEY, AND WILLIAM E.. CAPEN, OF NEW YORK, N. Y., ASSIGNORS TO WESTERN ELECTRIC COMPANY, lNCORPORATED, OF NEW YORK, N. Y., A CORPORATION F NEW YORK.

TELEGRAPHONE.

Specification of Letters Patent.

Patented Jan. 25, 1921.

Application led October 28, 1916. Serial No. 128,322.

l States, residing at llainfield, in the county of Union and State of New Jerse and at New York, in the county of New ork and State of New York, respectively, have invented certain new and useful Improvements in Telegraphones, of which the following is a full, clear, concise, and exact description.

This invention relates to a speech-recording and reproducin device of the type known in the art as t e telegraphone It is an object of the present invention to generally improve the construction and efiiciency of a device of this character and to adapt it for use in telephone exchange systems for the purpose of reproducing spoken telephone numbers in accordance with the set position of a manually operable device. In order to accomplish this function, it is necessary to provide a plurality of recording and reproducing paths upon each of which a single number is recorded, so that when the circuit of the reproducing magnet individual to such path is extended to a telephone, the number recorded on such path will be repeated.

The particular circuit arrangement which may be employed for this purpose forms no part of the present invention, and hence will not be disclosed or described herein.

It has been found byeXperiment that when recording and reproducing coils of the ordinary construction are used, there is a tendency for the magnetic record produced thereby on the magnetic recording medium to creep, which tends to reduce the permanency and quality of the record. In accordance with a feature of the present invention, this tendency is reduced by an improved construction of the core of the recording and reproducing coils, which provides a plurality of pole pieces, preferably three in number. The core is thus substantially E-shaped and the magnetizing coil itself is placed upon the middle pole-piece, which becomes the active pole-piece. Also, in accordance with this feature of the invention, the projecting end of the active pole-piece is beveled to present a fine edge to improve the quality'of the record, whereas the outside pole-pieces are provided with flat faces substantially parallel to the surface of the recording medium, in order that the reluctance of the ma etic circuit may be a minimum.

ther features of the invention relate to the method of mounting the erasing coils, the provision of adjustments for the recording and reproducing coils and the erasing coils, and the means employed for producing a record and for erasing the record preparatory to the production of a new record.

These and other features 0f the invention will more clearly appear from a consideration of the detailed specification and the accompanying drawings in which- Figure 1 is a front elevation of the device as a whole;

Fig. 2 is an end view taken on the line 2-2 of Fig. 1;

Figs. 3 and 4 are enlarged views of a recordlng and reproducing coil and its support;

Figs. 5 and 6 are similar views of an erasin coil;

ig. 7 is a diagram of the circuit employed in recording and reproducing a record; and

Fig. 8 is a diagram of the circuit employed for erasing a record.

The device as a whole is mounted upon a base l upon which are supported a plurality of standards 2. The upper ends of such standards are provided with bearings 3 which serve to support a shaft 4, upon which shaft are mounted recording disks 5. These disks are of steel, are mounted in pairs on either side of the spacing members 6 and are held between such spacing members and a pair of collars 7. Each pair of disks is further clamped together by means of suitable rivets 8, which construction prevents warping of the disks. Mounted on each of the supports 2 are segments 9, all of which ma be of identical construction and one of which is shown more in detail in Fig. 2. These segments are supported on the standards 2 by means of suitable arms 10. The shaft carriesat one end a pulleyll, which is adapted to be driven through a belt 12 from a motor 13. Mounted in slots 14 on the segments 9 are a plurality 0f recording and reproducing coils 15, shown in detail in Figs. 3 and 4. As shown in Fig. 2, the various slots 14 are concentric, and during the movement of the disks the recording coils travel over concentric circular paths on such disks.

Referring now to Figs. 3 and 4, the recording and reproducing coils are supported on the segments 9 by means of a rojecting lug or bracket indicated at 65. ecured to such bracket by means of, screws 16, are a pair of lugs 17, which are adapted to fit in the slots 14, as more clearly indicated in Fig. 2, and serve to prevent rotation of such bracket about the thumb-screw 18, the shank of which passes through the slot 14 and into the standard 65. By loosening the thumbscrew 18, the standard can be adjusted along the length of the slot. Pivoted to the standard by means of the screws 19, is a lever 20, to the outer end of which the reproducing coil 15 is detachably secured. The outer end of the lever 20 is bifurcated, forming a lower portion 21 and an upper portion 22, between which an extension of the core 23 of the reproducing and recording coil is adapted to be engaged. As is more clearly shown in Fig. 4 the core piece 23 of the recording and reproducing coil is in the form of a fla-t substantially E-shaped piece of silicon steel, the coil being placed upon the middle projection 25 of the E. As is clearly shown in Fig. 3, the outer end of the lever 20 is inclined to the plane of the recording disk, and the outer end of the middle branch 25 of the pole-piece, which passes through the recording and reproducing coil, is brought to a sharp edge by means of a bevel which is substantially perpendicular to the plane of the recording disk. The two outer branches of the pole-piece, however, are beveled in the opposite direction so as to present a surface which is substantially parallel to the.plane of the recording disk. The pole-piece 23 is provided with a pair of studs indicated at 24, which are adapted to pass under and to be held by apair of springs indicatedI at 55, one end of such springs being attached to the lever 20 and the other end being provided with a cup-shaped portion adapted to engage the head of the stud 24. By virtue of thisconstruction itis possible to attach the olepiece and recording coil carried there y to the armr20 by merely slipping the pole-piece into the bifurcation in the end of the lever 2O with the studs 24 engaging the cup shaped ends of the spring 55. The spring indicated at 56 is mounted on the bracket 65 with its free end bearing against the lever 20, tending to rotate such lever about 'its pivot and to maintain the project ing pole-piece of the recording coil in yielding contact with the recording,disks.

The erasing coils 26 are also mounted on the segment 9 and are positioned so as to follow the same concentric paths, on the steel disks as are followed by the recording and reproducing coils 15. These erasing coils are wound upon a substantially fiat core 41, the outer end of which is beveled in order to present a sharp edge to the surface isteria of the disk 5. The core .is supported on .a lever 27, the outer inclined end of which 1s provided with a bifurcated portion, providing a slot between the portions 28 and 29, in which the inner end ofthe pole-piece 41 is adapted to be inserted. The pole-piece 41 also carries a pair of studs 30 which are adapted to be engaged by the cup-shaped ends of a pair of retaining springs 31, which are mounted on the lever 27. The lever 27 is pivoted at 32 on a bracket 33, which bracket passes through a slot 34 in the supporting segment 9. The bracket 33 is secured to a shaft 35 which is rotatably mounted 'in bearings 36 secured to the segment 9. The upper end of the shaft 35 is provided with a small hand wheel 37 by means of which. the bracket 33 and the parts carried thereby may be rotated away from the disks 5. The bracket 33 is provided with a plurality of depressions 38 and 39 with which the end of a retaining spring 40 is adapted to coperate to hold the lever 33 in one of two positions. To the bracket 33 is attached one end of a 'spring 42, the other end of which bears upon one end of the lever 27 and tends to hold the end of the erasing coil core in yielding engagement with the disk 5. The movement of the lever 27 about its pivot under the influence of spring 42 is limited by a suitable pin or stop 54. It will be observed that the outer end of the lever 27 is inclined to the plane of the disk 5 so that the pole-piece of the erasing coil 26 is also inclined to the plane of the disk 5. The inclined mounting of the pole-pieces of the recording and reproducing coils and the erasing coil is for the purpose of reducing friction.

As shown more clearly in Fig. 2,there are two sets of recording and reproducing coils and a single set of erasing coils, providing two reproducing and recording coils for each recording path on the disk, the object of this arrangement being to permit the simultaneous recording of numbers at two different points in the same recording path.

While the` numbers are being recorded and reproduced, the lerasing coils are rotated away from the disks by means of the hand wheels 37.

In preparing the record for the particularapparatus for which the device is adapted to be used, the circuit arrangement indicated in Fig. 7 is employed. The record impressed upon each recording path consists of a single number such as 1, 2 or 3, etc., reproduced throughout the entire recording path. In order that these numbers rwhen recorded shall be properly spaced for reproducing, and shall not overlap, a commutator indicated at 49 is provided, this commutator being driven by means of gears 43 from the shaft 4. A plurality of brushes indicated at 45 engage with the commutator and pilot lamps, adapted to be illuminated through such commutator when various portions of the disk are positioned underneath the recording and reproducing coils, serve to indicate to the person making the record when the number should be spoken.

As the same number is to be repeated a number of times in the same recording path, it is of advantage to simultaneously record such number on a plurality of points in the same recording path on the disks. In the particular embodiment of the invention disclosed, this is accomplished by using two recording and reproducing coils which are spaced approximately 180 degrees from one another on the circular recording path, and which are adapted to be connected in series with a telephone transmitter. As shown in Fig. 7, when the double pole switch 50 is thrown to the right, the two recording and reproducing coils are connected in series in a circuit including a source of potential 44, a telephone transmitter 51, an inductance 46 and a capacity 47. Thus when the number to be recorded is spoken in the transmitter 5l, the recording and reproducing coils 15 act to locally magnetize portions of the recording disk 5 at points 180 degrees apart. When it is desired to reproduce the numbers thus recorded, switch 50 is thrown to the left, thus connecting the recording and reproducing coils with the telephone receiver 48. In actual practice when the device is employed in a telephone system, the recording and reproducing coils are connected through various instrumentalities with the telephone receiver of an operator and the various recording and reproducing coils are successively connected to the receiver of such operator in order to repeat several digits of a number. For example, in order to repeat the numbers 1-2-3-4, the recording and reproducing coils individual to the path on the disk upon which the number l was recorded, will lirst be switched in,- and then the recording and reproducing coils upon which the numbers 2-3-4 have been recorded, will be successively switched in.

As the records produced on the disks are not of a permanent nature, it is necessary at definite intervals to erase such records and to impress new records thereon. This erasing is accomplished by means of the erasing coils, previously described, which are adjusted in proximity with the disks and connected in the circuit arrangement shown in Fig. 8. When the switch indicated at 53 is thrown to the left, current is sent through the erasing coil 26 from a source of potential indicated at 52. This current is of suiiicient value to raise the steel of the disk to the saturation point in the path of the particular erasing coil employed. This current is maintained during several revolutions of the disk, and then the switch 53 is thrownl to the right, reversing the current and reducing the current to such a value that the steel is practically demagnetized, and any record or extraneous noise on the disk is erased. If necessary, the current can be still further reduced by means of the variable resistance indicated at 52.

What is claimed is:

1. In a telegraphone, a magnetic recording medium, a recording andy reproducing coil pivotally. movable relative thereto, and a magnetic core provided with an active pole piece and a plurality of inactive pole-pieces, said active pole-piece engaging said recording medium and serving to support such re cording and reproducing coil and said inactive pole pieces being spaced from said recording medium.

2. In a telegraphone, a magnetic recording medium having a smooth surface, a recording and reproducing coil associated with said recording medium, and a substantially E- shaped core upon the center branch of which .such coil is mounted, said center branch only having contact with said recording medium.

3. A telegraphone comprising a rotatable magnetic disk and a plurality of recording and reproducing coils mounted at different radial distances from the center of rotation of said disk, whereby a plurality of independent records may be impressed on said disllcl in a plurality of concentric circular pat s.

4. A telegraphone comprising a rotatable magnetic disk and a plurality of recording and reproducing coils'mounted at different radial distances from the center of said disk, and means for independently adjusting said coils in the circular paths about the center of rotation of said disk.

5. A telegraphone comprising a rotatable magnetic disk, a plurality of recording and reproducing coils adapted to be included in a single recording and reproducing circuit, and means for positioning said coils in angular spaced relation at equal radial distances from the center of rotation of the disk, whereby a plurality of identical records may be simultaneously produced in a single recording path on the disk.

6. A telegraphone comprising a movable recording medium, recording and reproducing coils for producing a record on said recording medium, an erasing coil positioned adjacent such recording medium, and a support for said erasing coil adapted to support the same in operative and inoperative positions.

7. A telegraphone comprising a recording medium, reproducing and recording coils, an erasing coil movable relative to said reproducing and recording coils, magnetic cores for said erasing coil pivotally mounted supports for said coils, and springs engag- `ing one end of such supports to maintain such cores in yielding Contact with the recording medium.

8. lin e. telegraphone, a magnetic recording medium having afsmooth recording surface, e recording and reproducing coil movable relative thereto, a ma etic core for such coil, and a plurality o pole pieces forming ai perm of sucheore upon one of which pole meedere pieces said coil is mounted, the latter pole 10 piece only being engaged with said recordin medium.

n witness whereof We hereunto subscribe ornames this 27th day of October, A. D. 1 1

HARRY B. Winn. WiLLIAM H. CAPEN. 

